Subtract 21/9 from 30/70
1st number: 30/70, 2nd number: 2 3/9
30/70 - 21/9 is -40/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 9 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
30/70 = 30 × 9/70 × 9 = 270/630 - Likewise, for the 2nd fraction, since 9 × 70 = 630,
21/9 = 21 × 70/9 × 70 = 1470/630 - Subtract the two like fractions:
270/630 - 1470/630 = 270 - 1470/630 = -1200/630 - After reducing the fraction, the answer is -40/21
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